/* --mode:java; c-basic-offset:2; -- */
/*
 * Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved. Redistribution and use in source and binary
 * forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions
 * of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2.
 * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
 * disclaimer in the documentation and/or other materials provided with the distribution. 3. The names of the authors
 * may not be used to endorse or promote products derived from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
 * INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/*
 * This program is based on zlib-1.1.3, so all credit should go authors Jean-loup Gailly(jloup@gzip.org) and Mark
 * Adler(madler@alumni.caltech.edu) and contributors of zlib.
 */

package net.sf.javadc.util.zlib;

final class InfBlocks
{
    static final private int   MANY            = 1440;

    // And'ing with mask[n] masks the lower n bits
    static final private int[] inflate_mask    =
                                                   { 0x00000000, 0x00000001, 0x00000003, 0x00000007, 0x0000000f,
                    0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff, 0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff,
                    0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff };

    // Table for deflate from PKZIP's appnote.txt.
    static final int[]         border          = { // Order of the bit length code lengths
                                                   16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 };

    static final private int   Z_OK            = 0;

    static final private int   Z_STREAM_END    = 1;

    static final private int   Z_NEED_DICT     = 2;

    static final private int   Z_ERRNO         = -1;

    static final private int   Z_STREAM_ERROR  = -2;

    static final private int   Z_DATA_ERROR    = -3;

    static final private int   Z_MEM_ERROR     = -4;

    static final private int   Z_BUF_ERROR     = -5;

    static final private int   Z_VERSION_ERROR = -6;

    static final private int   TYPE            = 0;                                                                   // get
                                                                                                                       // type
                                                                                                                       // bits
                                                                                                                       // (3,
                                                                                                                       // including
                                                                                                                       // end
                                                                                                                       // bit)

    static final private int   LENS            = 1;                                                                   // get
                                                                                                                       // lengths
                                                                                                                       // for
                                                                                                                       // stored

    static final private int   STORED          = 2;                                                                    // processing
                                                                                                                       // stored
                                                                                                                       // block

    static final private int   TABLE           = 3;                                                                   // get
                                                                                                                       // table
                                                                                                                       // lengths

    static final private int   BTREE           = 4;                                                                   // get
                                                                                                                       // bit
                                                                                                                       // lengths
                                                                                                                       // tree
                                                                                                                       // for
                                                                                                                       // a
                                                                                                                       // dynamic
    // block

    static final private int   DTREE           = 5;                                                                   // get
                                                                                                                       // length,
                                                                                                                       // distance
                                                                                                                       // trees
                                                                                                                       // for
                                                                                                                       // a
    // dynamic block

    static final private int   CODES           = 6;                                                                   // processing
                                                                                                                       // fixed
                                                                                                                       // or
                                                                                                                       // dynamic
                                                                                                                       // block

    static final private int   DRY             = 7;                                                                   // output
                                                                                                                       // remaining
                                                                                                                       // window
                                                                                                                       // bytes

    static final private int   DONE            = 8;                                                                   // finished
                                                                                                                       // last
                                                                                                                       // block,
                                                                                                                       // done

    static final private int   BAD             = 9;                                                                   // ot
                                                                                                                       // a
                                                                                                                       // data
                                                                                                                       // error--stuck
                                                                                                                       // here

    int                        mode;                                                                                  // current
                                                                                                                       // inflate_block
                                                                                                                       // mode

    int                        left;                                                                                  // if
                                                                                                                       // STORED,
                                                                                                                       // bytes
                                                                                                                       // left
                                                                                                                       // to
                                                                                                                       // copy

    int                        table;                                                                                 // table
                                                                                                                       // lengths
                                                                                                                       // (14
                                                                                                                       // bits)

    int                        index;                                                                                 // index
                                                                                                                       // into
                                                                                                                       // blens
                                                                                                                       // (or
                                                                                                                       // border)

    int[]                      blens;                                                                                 // bit
                                                                                                                       // lengths
                                                                                                                       // of
                                                                                                                       // codes

    int[]                      bb              = new int[1];                                                          // bit
                                                                                                                       // length
                                                                                                                       // tree
                                                                                                                       // depth

    int[]                      tb              = new int[1];                                                          // bit
                                                                                                                       // length
                                                                                                                       // decoding
                                                                                                                       // tree

    InfCodes                   codes;                                                                                 // if
                                                                                                                       // CODES,
                                                                                                                       // current
                                                                                                                       // state

    int                        last;                                                                                  // true
                                                                                                                       // if
                                                                                                                       // this
                                                                                                                       // block
                                                                                                                       // is
                                                                                                                       // the
                                                                                                                       // last
                                                                                                                       // block

    // mode independent information
    int                        bitk;                                                                                  // bits
                                                                                                                       // in
                                                                                                                       // bit
                                                                                                                       // buffer

    int                        bitb;                                                                                  // bit
                                                                                                                       // buffer

    int[]                      hufts;                                                                                 // single
                                                                                                                       // malloc
                                                                                                                       // for
                                                                                                                       // tree
                                                                                                                       // space

    byte[]                     window;                                                                                // sliding
                                                                                                                       // window

    int                        end;                                                                                   // one
                                                                                                                       // byte
                                                                                                                       // after
                                                                                                                       // sliding
                                                                                                                       // window

    int                        read;                                                                                  // window
                                                                                                                       // read
                                                                                                                       // pointer

    int                        write;                                                                                 // window
                                                                                                                       // write
                                                                                                                       // pointer

    Object                     checkfn;                                                                               // check
                                                                                                                       // function

    long                       check;                                                                                 // check
                                                                                                                       // on
                                                                                                                       // output

    InfBlocks(
        ZStream z,
        Object checkfn,
        int w )
    {
        hufts = new int[MANY * 3];
        window = new byte[w];
        end = w;
        this.checkfn = checkfn;
        mode = TYPE;
        reset( z, null );
    }

    void free(
        ZStream z )
    {
        reset( z, null );
        window = null;
        hufts = null;
        // ZFREE(z, s);
    }

    // copy as much as possible from the sliding window to the output area
    int inflate_flush(
        ZStream z,
        int r )
    {
        int n;
        int p;
        int q;

        // local copies of source and destination pointers
        p = z.next_out_index;
        q = read;

        // compute number of bytes to copy as far as end of window
        n = ((q <= write ? write : end) - q);
        if ( n > z.avail_out )
        {
            n = z.avail_out;
        }
        if ( n != 0 && r == Z_BUF_ERROR )
        {
            r = Z_OK;
        }

        // update counters
        z.avail_out -= n;
        z.total_out += n;

        // update check information
        if ( checkfn != null )
        {
            z.adler = check = z._adler.adler32( check, window, q, n );
        }

        // copy as far as end of window
        System.arraycopy( window, q, z.next_out, p, n );
        p += n;
        q += n;

        // see if more to copy at beginning of window
        if ( q == end )
        {
            // wrap pointers
            q = 0;
            if ( write == end )
            {
                write = 0;
            }

            // compute bytes to copy
            n = write - q;
            if ( n > z.avail_out )
            {
                n = z.avail_out;
            }
            if ( n != 0 && r == Z_BUF_ERROR )
            {
                r = Z_OK;
            }

            // update counters
            z.avail_out -= n;
            z.total_out += n;

            // update check information
            if ( checkfn != null )
            {
                z.adler = check = z._adler.adler32( check, window, q, n );
            }

            // copy
            System.arraycopy( window, q, z.next_out, p, n );
            p += n;
            q += n;
        }

        // update pointers
        z.next_out_index = p;
        read = q;

        // done
        return r;
    }

    int proc(
        ZStream z,
        int r )
    {
        int t; // temporary storage
        int b; // bit buffer
        int k; // bits in bit buffer
        int p; // input data pointer
        int n; // bytes available there
        int q; // output window write pointer
        int m; // bytes to end of window or read pointer

        // copy input/output information to locals (UPDATE macro restores)
        {
            p = z.next_in_index;
            n = z.avail_in;
            b = bitb;
            k = bitk;
        }
        {
            q = write;
            m = (q < read ? read - q - 1 : end - q);
        }

        // process input based on current state
        while ( true )
        {
            switch ( mode )
            {
                case TYPE:

                    while ( k < 3 )
                    {
                        if ( n != 0 )
                        {
                            r = Z_OK;
                        }
                        else
                        {
                            bitb = b;
                            bitk = k;
                            z.avail_in = n;
                            z.total_in += p - z.next_in_index;
                            z.next_in_index = p;
                            write = q;
                            return inflate_flush( z, r );
                        }
                        ;
                        n--;
                        b |= (z.next_in[p++] & 0xff) << k;
                        k += 8;
                    }
                    t = (b & 7);
                    last = t & 1;

                    switch ( t >>> 1 )
                    {
                        case 0: // stored
                        {
                            b >>>= 3;
                            k -= 3;
                        }
                            t = k & 7; // go to byte boundary

                            {
                                b >>>= t;
                                k -= t;
                            }
                            mode = LENS; // get length of stored block
                            break;
                        case 1: // fixed
                        {
                            int[] bl = new int[1];
                            int[] bd = new int[1];
                            int[][] tl = new int[1][];
                            int[][] td = new int[1][];

                            InfTree.inflate_trees_fixed( bl, bd, tl, td, z );
                            codes = new InfCodes( bl[0], bd[0], tl[0], td[0], z );
                        }

                            {
                                b >>>= 3;
                                k -= 3;
                            }

                            mode = CODES;
                            break;
                        case 2: // dynamic

                        {
                            b >>>= 3;
                            k -= 3;
                        }

                            mode = TABLE;
                            break;
                        case 3: // illegal

                        {
                            b >>>= 3;
                            k -= 3;
                        }
                            mode = BAD;
                            z.msg = "invalid block type";
                            r = Z_DATA_ERROR;

                            bitb = b;
                            bitk = k;
                            z.avail_in = n;
                            z.total_in += p - z.next_in_index;
                            z.next_in_index = p;
                            write = q;
                            return inflate_flush( z, r );
                    }
                    break;
                case LENS:

                    while ( k < 32 )
                    {
                        if ( n != 0 )
                        {
                            r = Z_OK;
                        }
                        else
                        {
                            bitb = b;
                            bitk = k;
                            z.avail_in = n;
                            z.total_in += p - z.next_in_index;
                            z.next_in_index = p;
                            write = q;
                            return inflate_flush( z, r );
                        }
                        ;
                        n--;
                        b |= (z.next_in[p++] & 0xff) << k;
                        k += 8;
                    }

                    if ( (~b >>> 16 & 0xffff) != (b & 0xffff) )
                    {
                        mode = BAD;
                        z.msg = "invalid stored block lengths";
                        r = Z_DATA_ERROR;

                        bitb = b;
                        bitk = k;
                        z.avail_in = n;
                        z.total_in += p - z.next_in_index;
                        z.next_in_index = p;
                        write = q;
                        return inflate_flush( z, r );
                    }
                    left = b & 0xffff;
                    b = k = 0; // dump bits
                    mode = left != 0 ? STORED : last != 0 ? DRY : TYPE;
                    break;
                case STORED:
                    if ( n == 0 )
                    {
                        bitb = b;
                        bitk = k;
                        z.avail_in = n;
                        z.total_in += p - z.next_in_index;
                        z.next_in_index = p;
                        write = q;
                        return inflate_flush( z, r );
                    }

                    if ( m == 0 )
                    {
                        if ( q == end && read != 0 )
                        {
                            q = 0;
                            m = (q < read ? read - q - 1 : end - q);
                        }
                        if ( m == 0 )
                        {
                            write = q;
                            r = inflate_flush( z, r );
                            q = write;
                            m = (q < read ? read - q - 1 : end - q);
                            if ( q == end && read != 0 )
                            {
                                q = 0;
                                m = (q < read ? read - q - 1 : end - q);
                            }
                            if ( m == 0 )
                            {
                                bitb = b;
                                bitk = k;
                                z.avail_in = n;
                                z.total_in += p - z.next_in_index;
                                z.next_in_index = p;
                                write = q;
                                return inflate_flush( z, r );
                            }
                        }
                    }
                    r = Z_OK;

                    t = left;
                    if ( t > n )
                    {
                        t = n;
                    }
                    if ( t > m )
                    {
                        t = m;
                    }
                    System.arraycopy( z.next_in, p, window, q, t );
                    p += t;
                    n -= t;
                    q += t;
                    m -= t;
                    if ( (left -= t) != 0 )
                    {
                        break;
                    }
                    mode = last != 0 ? DRY : TYPE;
                    break;
                case TABLE:

                    while ( k < 14 )
                    {
                        if ( n != 0 )
                        {
                            r = Z_OK;
                        }
                        else
                        {
                            bitb = b;
                            bitk = k;
                            z.avail_in = n;
                            z.total_in += p - z.next_in_index;
                            z.next_in_index = p;
                            write = q;
                            return inflate_flush( z, r );
                        }
                        ;
                        n--;
                        b |= (z.next_in[p++] & 0xff) << k;
                        k += 8;
                    }

                    table = t = b & 0x3fff;
                    if ( (t & 0x1f) > 29 || (t >> 5 & 0x1f) > 29 )
                    {
                        mode = BAD;
                        z.msg = "too many length or distance symbols";
                        r = Z_DATA_ERROR;

                        bitb = b;
                        bitk = k;
                        z.avail_in = n;
                        z.total_in += p - z.next_in_index;
                        z.next_in_index = p;
                        write = q;
                        return inflate_flush( z, r );
                    }
                    t = 258 + (t & 0x1f) + (t >> 5 & 0x1f);
                    blens = new int[t];

                    {
                        b >>>= 14;
                        k -= 14;
                    }

                    index = 0;
                    mode = BTREE;
                case BTREE:
                    while ( index < 4 + (table >>> 10) )
                    {
                        while ( k < 3 )
                        {
                            if ( n != 0 )
                            {
                                r = Z_OK;
                            }
                            else
                            {
                                bitb = b;
                                bitk = k;
                                z.avail_in = n;
                                z.total_in += p - z.next_in_index;
                                z.next_in_index = p;
                                write = q;
                                return inflate_flush( z, r );
                            }
                            ;
                            n--;
                            b |= (z.next_in[p++] & 0xff) << k;
                            k += 8;
                        }

                        blens[border[index++]] = b & 7;

                        {
                            b >>>= 3;
                            k -= 3;
                        }
                    }

                    while ( index < 19 )
                    {
                        blens[border[index++]] = 0;
                    }

                    bb[0] = 7;
                    t = InfTree.inflate_trees_bits( blens, bb, tb, hufts, z );
                    if ( t != Z_OK )
                    {
                        r = t;
                        if ( r == Z_DATA_ERROR )
                        {
                            blens = null;
                            mode = BAD;
                        }

                        bitb = b;
                        bitk = k;
                        z.avail_in = n;
                        z.total_in += p - z.next_in_index;
                        z.next_in_index = p;
                        write = q;
                        return inflate_flush( z, r );
                    }

                    index = 0;
                    mode = DTREE;
                case DTREE:
                    while ( true )
                    {
                        t = table;
                        if ( !(index < 258 + (t & 0x1f) + (t >> 5 & 0x1f)) )
                        {
                            break;
                        }

                        int[] h;
                        int i, j, c;

                        t = bb[0];

                        while ( k < t )
                        {
                            if ( n != 0 )
                            {
                                r = Z_OK;
                            }
                            else
                            {
                                bitb = b;
                                bitk = k;
                                z.avail_in = n;
                                z.total_in += p - z.next_in_index;
                                z.next_in_index = p;
                                write = q;
                                return inflate_flush( z, r );
                            }
                            ;
                            n--;
                            b |= (z.next_in[p++] & 0xff) << k;
                            k += 8;
                        }

                        if ( tb[0] == -1 )
                        {
                            // System.err.println("null...");
                        }

                        t = hufts[(tb[0] + (b & inflate_mask[t])) * 3 + 1];
                        c = hufts[(tb[0] + (b & inflate_mask[t])) * 3 + 2];

                        if ( c < 16 )
                        {
                            b >>>= t;
                            k -= t;
                            blens[index++] = c;
                        }
                        else
                        { // c == 16..18
                            i = c == 18 ? 7 : c - 14;
                            j = c == 18 ? 11 : 3;

                            while ( k < t + i )
                            {
                                if ( n != 0 )
                                {
                                    r = Z_OK;
                                }
                                else
                                {
                                    bitb = b;
                                    bitk = k;
                                    z.avail_in = n;
                                    z.total_in += p - z.next_in_index;
                                    z.next_in_index = p;
                                    write = q;
                                    return inflate_flush( z, r );
                                }
                                ;
                                n--;
                                b |= (z.next_in[p++] & 0xff) << k;
                                k += 8;
                            }

                            b >>>= t;
                            k -= t;

                            j += b & inflate_mask[i];

                            b >>>= i;
                            k -= i;

                            i = index;
                            t = table;
                            if ( i + j > 258 + (t & 0x1f) + (t >> 5 & 0x1f) || c == 16 && i < 1 )
                            {
                                blens = null;
                                mode = BAD;
                                z.msg = "invalid bit length repeat";
                                r = Z_DATA_ERROR;

                                bitb = b;
                                bitk = k;
                                z.avail_in = n;
                                z.total_in += p - z.next_in_index;
                                z.next_in_index = p;
                                write = q;
                                return inflate_flush( z, r );
                            }

                            c = c == 16 ? blens[i - 1] : 0;
                            do
                            {
                                blens[i++] = c;
                            }
                            while ( --j != 0 );
                            index = i;
                        }
                    }

                    tb[0] = -1;
                    {
                        int[] bl = new int[1];
                        int[] bd = new int[1];
                        int[] tl = new int[1];
                        int[] td = new int[1];
                        InfCodes c;

                        bl[0] = 9; // must be <= 9 for lookahead assumptions
                        bd[0] = 6; // must be <= 9 for lookahead assumptions
                        t = table;
                        t =
                            InfTree.inflate_trees_dynamic( 257 + (t & 0x1f), 1 + (t >> 5 & 0x1f), blens, bl, bd, tl,
                                td, hufts, z );
                        if ( t != Z_OK )
                        {
                            if ( t == Z_DATA_ERROR )
                            {
                                blens = null;
                                mode = BAD;
                            }
                            r = t;

                            bitb = b;
                            bitk = k;
                            z.avail_in = n;
                            z.total_in += p - z.next_in_index;
                            z.next_in_index = p;
                            write = q;
                            return inflate_flush( z, r );
                        }

                        codes = new InfCodes( bl[0], bd[0], hufts, tl[0], hufts, td[0], z );
                    }
                    blens = null;
                    mode = CODES;
                case CODES:
                    bitb = b;
                    bitk = k;
                    z.avail_in = n;
                    z.total_in += p - z.next_in_index;
                    z.next_in_index = p;
                    write = q;

                    if ( (r = codes.proc( this, z, r )) != Z_STREAM_END )
                    {
                        return inflate_flush( z, r );
                    }
                    r = Z_OK;
                    codes.free( z );

                    p = z.next_in_index;
                    n = z.avail_in;
                    b = bitb;
                    k = bitk;
                    q = write;
                    m = (q < read ? read - q - 1 : end - q);

                    if ( last == 0 )
                    {
                        mode = TYPE;
                        break;
                    }
                    mode = DRY;
                case DRY:
                    write = q;
                    r = inflate_flush( z, r );
                    q = write;
                    m = (q < read ? read - q - 1 : end - q);
                    if ( read != write )
                    {
                        bitb = b;
                        bitk = k;
                        z.avail_in = n;
                        z.total_in += p - z.next_in_index;
                        z.next_in_index = p;
                        write = q;
                        return inflate_flush( z, r );
                    }
                    mode = DONE;
                case DONE:
                    r = Z_STREAM_END;

                    bitb = b;
                    bitk = k;
                    z.avail_in = n;
                    z.total_in += p - z.next_in_index;
                    z.next_in_index = p;
                    write = q;
                    return inflate_flush( z, r );
                case BAD:
                    r = Z_DATA_ERROR;

                    bitb = b;
                    bitk = k;
                    z.avail_in = n;
                    z.total_in += p - z.next_in_index;
                    z.next_in_index = p;
                    write = q;
                    return inflate_flush( z, r );

                default:
                    r = Z_STREAM_ERROR;

                    bitb = b;
                    bitk = k;
                    z.avail_in = n;
                    z.total_in += p - z.next_in_index;
                    z.next_in_index = p;
                    write = q;
                    return inflate_flush( z, r );
            }
        }
    }

    void reset(
        ZStream z,
        long[] c )
    {
        if ( c != null )
        {
            c[0] = check;
        }
        if ( mode == BTREE || mode == DTREE )
        {
            blens = null;
        }
        if ( mode == CODES )
        {
            codes.free( z );
        }
        mode = TYPE;
        bitk = 0;
        bitb = 0;
        read = write = 0;

        if ( checkfn != null )
        {
            z.adler = check = z._adler.adler32( 0L, null, 0, 0 );
        }
    }

    void set_dictionary(
        byte[] d,
        int start,
        int n )
    {
        System.arraycopy( d, start, window, 0, n );
        read = write = n;
    }

    // Returns true if inflate is currently at the end of a block generated
    // by Z_SYNC_FLUSH or Z_FULL_FLUSH.
    int sync_point()
    {
        return mode == LENS ? 1 : 0;
    }
}
